Storm Lorenzo: October 3/4 2019 **Technical Discussion Only**

Gaoth Laidir

TheRiverman wrote: »

It will not be a hurricane if it hits or comes close to us.Am I right in thinking that Ophelia still had Hurricane status when it hit us two years ago.

No, it was extratropical.

The ADT estimate is back up to 70 knots now. Still 10-15 knots lower than forecast. Wonder will this be reflected in the NHC update. The site is still showing 105 mph (90 knots).

donal.hunt

Pangea wrote: »

Do we think that a red alert will be issued if it hits us directly?

No. Current forecasts indicate the storm will have weakened significantly.

sdanseo

12Z ECM brings the centre east, from Sligo roughly to Dublin.

Widespread >130km/h gusts.

pad199207

That track could be a real rain maker.

Looks like Lorenzo could do a Dorian with that sharp turn.

CirrusBusiness

Pangea wrote: »

Do we think that a red alert will be issued if it hits us directly?

If Lorenzo's wind speed reached Red Level criteria, then yes, a red warning would be issued for the affected region. Also, timing of an arrival would play a substantial part in that planning I'm sure.

This is far from "GAME OVER" just yet.

sdanseo

pad199207 wrote: »

That track could be a real rain maker.

Looks like Lorenzo could do a Dorian with that sharp turn.

There would be 24hrs of continuous light to moderate horizontal rain with this ECM evolution.

24hrs to 7am Friday accumulated

kenmc

A red warning on Thursday would be perfect. Match kicks off at 11.15, most folk wouldn't even have to pull a sickie!

km79

Oh yay
Rain

ninebeanrows

sdanseo wrote: »

12Z ECM brings the centre east, from Sligo roughly to Dublin.

Widespread >130km/h gusts.

Thanks for post but there are widespread 100kph gusts not 130kph just for clarity

TTLF

sdanseo wrote: »

12Z ECM brings the centre east, from Sligo roughly to Dublin.

Widespread >130km/h gusts.

Any charts passed 4am or is that all we have for now?

Meteorite58

ECM 12Z showing by then ex tropical storm Lorenzo at 964 hPa to the SW and deepens off the W coast to 955 hPa.

On this run it would have the strong winds developing towards early evening on Western coasts and continuing across the country overnight into Fri morning , clearing the SE / E coasts early Fri.

Stormy along the Atlantic coasts, very windy overland if not stormy . Heavy rain in W and N midlands on the present chart.

To note looks like could be rough weather to follow during the weekend.

Just the current run. Bit to go yet but a lot of the models seem to be showing Ireland having some impact from this.

sdanseo

Sleety_Rain wrote: »

Thanks for post but there are widespread 100kph gusts not 130kph just for clarity

Please dont quote pictures

Zoomed in. Maybe these are all hilltops / more exposed?

DOCARCH

sdanseo wrote: »

Please dont quote pictures

Mod Note: +1

When quoting, please delete links to images to avoid cluttering the thread.

Meteorite58

ninebeanrows

sdanseo wrote: »

Please dont quote pictures

Zoomed in. Maybe these are all hilltops / more exposed?

Is widespread now 5km inland of exposed Atlantic coast?

Apologies i just read your post and thought 130kph gusts widespread over Ireland but in reality it was 90-100kph with 130kph confined to near western coasts

Meteorite58

UKMO remarkably similar track and strength at this stage.

Gaoth Laidir

There's been a fair change in structure this afternoon, with the deep convection now switching from the eastern side to the west.

1823Z




1551Z

Gaoth Laidir

Alternative view of NHC forecast. The 34-knot (gale force) winds just touching the west coast at 12Z on Thursday as max intensity is 60 knots. 12Z Friday intensity 50 knots.

Good to see that in the nearer term the track is slightly more west of the Azores, so reducing the overall effects there.

Darwin

Interesting, wonder why the NHC don't see it being swept up in the Jetstream and shunted east.

Meteorite58

Big change in the models today ( Met Eireann quickly dropped the line where it said nothing exceptional expected ).

GFS 12Z , GEM 12Z looking almost identical bringing the remnants crossing Ireland as it fills ( currently looks like windy to strong winds ).

ARPEGE strong winds over much of Ireland ( stormy in parts ) . ICON windy along the coasts, staying off shore for the most part.

UKMO strong winds over Ireland and ECM just out looks very windy if not stormy in parts .

Currently the models look windy up to stormy in parts of the coasts, some showing very windy across the country up to stormy in parts.

In terms of predicting strengths , track etc a bit to go yet and expect changes but certainly the models look a lot more aligned this evening.

Gaoth Laidir

Just to show how bonkers it is, look at how different the track is between the Canadian ensemble mean (CEMN, sharp westerly turn towards Iceland) and the Control run (CC00), east over Ireland and into the North Sea. similar to the GFS mean (AEMN). The NHC official track (OFCL) slap right bang down the middle.

EDIT: The updated chart shows the GFS Op run (AVNO) heading off on the Orient Express...

Gaoth Laidir

Today's SHIPS runs are trending towards slightly lower intensity in the shorter term but marginally higher in the longer term as its track has been shifting west each time.

Meteorite58

Hurricane LORENZO
As of 18:00 UTC Sep 30, 2019:

Location: 30.3°N 42.6°W
Maximum Winds: 90 kt Gusts: nan kt
Minimum Central Pressure: 957 mb
Environmental Pressure: 1010 mb
Radius of Circulation: 300 NM
Radius of Maximum Wind: 25 NM

64 kt Wind Radii by Quadrant:

EUMETSAT

pauldry

I see now the reason Met Eireann are concerned.

At first storm runs up the West but then goes over the North with fierce winds

Tomorrow evening might be a different set of charts with just track up along West as was original idea . ( 60 per cent of time approx original idea wins, but id also say the threat of severe winds for the North and West is 60 per cent as of tonight. 2 days ago I would hv said 10 percent. )

Graces7

Sleety_Rain wrote: »

Is widespread now 5km inland of exposed Atlantic coast?

Apologies i just read your post and thought 130kph gusts widespread over Ireland but in reality it was 90-100kph with

130kph confined to near western coasts

Ouch...west mayo offshore island....

Graces7

pauldry wrote: »

I see now the reason Met Eireann are concerned.

At first storm runs up the West but then goes over the North with fierce winds

Tomorrow evening might be a different set of charts with just track up along West as was original idea . ( 60 per cent of time approx original idea wins, but id also say the threat of severe winds for the North and West is 60 per cent as of tonight. 2 days ago I would hv said 10 percent. )

That makes perfect sense. Thank you.

Gaoth Laidir

Comparison between the 12Z and 00Z ECM ensembles. Broadly similar, except for the change in the Mean and HRES tracks.

Sleety_Rain

Sleety_Rain wrote: »

Is widespread now 5km inland of exposed Atlantic coast?

Apologies i just read your post and thought 130kph gusts widespread over Ireland but in reality it was 90-100kph with 130kph confined to near western coasts

What is he getting all excited about? Sure it's only the Wesht!

crushproof

Certainly all the ships at sea are giving it a wide berth!

drunkmonkey

How's it compare to the likes of Christine, Ophelia etc for waves. Looks like 18ft's rolling into the west at high tide Thursday night.